Messages in this thread | | | Date | Sun, 15 Sep 2013 18:39:19 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH] kthread: Make kthread_create() killable. |
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On 09/15, Tetsuo Handa wrote: > > Oleg Nesterov wrote: > > I am wondering if this can be simplified... > > > > At least you can move create->done from kthread_create_info to the > > stack, and turn create->owner into the pointer to that completion. > > Use of DECLARE_COMPLETION_ONSTACK() looks harmful to me because current thread > needs to be able to terminate as soon as possible if SIGKILLed
Sure.
> If we move something from kmalloc()ed zone to stack, > current thread cannot be terminated until that something is guaranteed to no > longer be used.
Please look at call_usermodehelper_exec() which does this trick. The logic is the same, just you need to xchg(create->completion) instead of create->owner.
In any case "void *owner" looks strange. It is in fact boolean (in your patch). You can even use, say, test_and_set_bit() instead of xchg.
Oleg.
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